X0303 4 2011-02-08 0 0001396814 Pacira Pharmaceuticals, Inc. PCRX 0001055951 ORBIMED ADVISORS LLC 767 THIRD AVENUE, 30TH FLOOR NEW YORK NY 10017 0 0 1 0 0001432241 OrbiMed Capital GP III LLC 767 THIRD AVENUE, 30TH FLOOR NEW YORK NY 10017 0 0 1 0 0001055949 ISALY SAMUEL D 767 THIRD AVENUE, 30TH FLOOR NEW YORK NY 10017 0 0 1 0 Common Stock 2011-02-08 4 C 0 1473645 A 1566625 I See footnotes Common Stock 2011-02-08 4 C 0 14035 A 1580660 I See footnote Common Stock 2011-02-08 4 C 0 705845 13.44 A 2286505 I See footnotes Common Stock 2011-02-08 4 C 0 6722 13.44 A 2293227 I See footnote Common Stock 2011-02-08 4 P 0 265331 7.00 A 2558558 I See footnotes Common Stock 2011-02-08 4 P 0 2526 7.00 A 2561084 I See footnote Common Stock 2011-02-08 4 P 0 265330 7.00 A 2826414 I See footnotes Common Stock 2011-02-08 4 P 0 2527 7.00 A 2828941 I See footnote Series A Convertible Preferred Stock 2011-02-08 4 C 0 1473645 0 D Common Stock 1473645 0 I See footnote Series A Convertible Preferred Stock 2011-02-08 4 C 0 14035 0 D Common Stock 14035 0 I See footnote Convertible Promissory Notes 13.44 2011-02-08 4 C 0 705845 0 D Common Stock 705845 0 I See footnote Convertible Promissory Notes 13.44 2011-02-08 4 C 0 6722 0 D Common Stock 6722 0 I See footnote Represents shares of Common Stock acquired upon the automatic conversion of Series A convertible preferred stock upon the closing of the Issuer's initial public offering of Common Stock. The Series A convertible preferred stock did not have an expiration date. The Series A convertible preferred stock automatically converted into shares of Common Stock at an effective conversion ratio of one-to-one upon the closing of the Issuer's initial public offering of Common Stock. These securities are held of record by OrbiMed Private Investments III, LP ("OPI") and may be deemed to be indirectly beneficially owned by OrbiMed Capital GP III LLC ("Capital"), OrbiMed Advisors LLC ("Advisors") and Samuel D. Isaly ("Isaly"). Capital is the sole general partner of OPI. Advisors, a registered adviser under the Investment Advisers Act of 1940, as amended, is the sole managing member of Capital. By virtue of such relationships, Capital and Advisors have discretionary investment management authority with respect to the assets of OPI. Such authority includes the power to vote and otherwise dispose of the securities held by OPI. Isaly, a natural person, also has investment and voting power over the securities held by OPI in his capacity as the managing member of, and holder of a controlling interest, in Advisors. As a result, each of Capital, Advisors and Isaly may be deemed to have beneficial ownership of the securities held by OPI. These securities are held of record by OrbiMed Associates III, LP ("Associates") and may be deemed to be indirectly beneficially owned by Advisors and Isaly. Advisors is the sole general partner of Associates. By virtue of such relationship, Advisors has discretionary investment management authority with respect to the assets of Associates. Such authority includes the power to vote and otherwise dispose of securities held by Associates. Isaly also has voting and investment power over the securities held by Associates in his capacity as the managing member of, and holder of a controlling interest, in Advisors. As a result, each of Advisors and Isaly may be deemed to have beneficial ownership of the securities held by Associates. This report on Form 4 is jointly filed by Capital, Advisors and Isaly. Each of the reporting persons disclaims beneficial ownership of the securities reported herein for purposes of Rule 16a-1(a) under the Securities Exchange Act of 1934, as amended (the "Exchange Act"), except to the extent of its or his pecuniary interest therein, if any. The reporting persons have designated a representative, currently Carl L. Gordon, a member of Advisors, to serve on the Issuer's board of directors. This report shall not be deemed an admission that the reporting persons are beneficial owners for the purpose of Section 16 of the Exchange Act, or for any other purpose. Represents shares of Common Stock acquired upon the automatic conversion of all principal and accrued interest due on convertible promissory notes upon the closing of the Issuer's initial public offering of Common Stock at an effective conversion price of approximately $13.44. These shares of Common Stock were acquired upon the conversion of convertible promissory notes exempt from the definition of a derivative security because the conversion price of such securities did not become fixed until their automatic conversion at the time of the closing of the Issuer's initial public offering of Common Stock. Represents shares of Common Stock acquired upon the conversion of convertible promissory notes issued in December 2010. The outstanding principal amount and accrued but unpaid interest therein was automatically converted into shares of Common Stock upon the closing of the Issuer's initial public offering of Common Stock at an effective conversion price of $7.00, which represents the initial public offering price per share of the Common Stock sold by the Issuer. These derivative securities are no longer beneficially owned. /s/ Samuel D. Isaly 2011-02-10